Mr. Alexander is principal at Alexander & Alexander, a firm that focuses on probate, trust and real estate law. His family's legal work in Chicago dates to the time of the Great Chicago Fire of 1871. For generations the family firm has represented the Elizabeth Morse and Elizabeth Morse Genius Charitable trusts, which doles out hundreds of thousands of dollars to nonprofit agencies and cultural institutions in Chicago.

Mr. Alexander, 63, a co-trustee of the trust, has been a Harris trustee since its inception, having served on the founding board of trustees. Since it opened in 2003, the Harris Theater for Music & Dance has played host to dozens of midsize performing arts companies that before then had no stage to call home.